The present project aims at an analysis of feto-maternal interactions in the immune system mediated by the trophoblast-specific Class I gene product, HLA-G. The assembly and intracellular transport pathways traveled by HLA-G will be examined in trophoblast cells of human origin. The availability of HLA-G transgenic mice, together with mice transgenic for HLA-A2/human beta2m or HLA-B27/human beta2m, as well as mice deficient for mouse beta2m, will allow a detailed characterization of the dependency of HLA-G on the presence of beta2m in vivo. The dependency of HLA-G expression on peptides delivered by the MHC-encoded peptide transporter TAP will be examined by measuring TAP-dependent peptide transport in vitro in human trophoblast cells, and by examining the expression of HLA-G in trophoblast of mice transgenic for HLA-G, crossed onto a homozygous TAP-1 deficient background. To facilitate immunohistochemical and biochemical analysis, antibodies against unfolded, bacterially produced HLA-G will be generated, in a manner analogous to that used for the production of anti HLA-A,B,C heavy chain MoAbs. The availability of polyclonal anti-mouse Class I heavy chain sera will allow a search for a mouse equivalent of HLA-G, using procedures that led to the identification of HLA-G in man. The biochemical characterization of a mouse equivalent for HLA-G would constitute a first step towards the identification of the Class I gene that encodes it. Expression of HLA-G in cultured human trophoblast will be examined both under normal circumstances and in cells infected with Herpes Simplex Virus (HSV) or Cytomegalovirus (CMV). Each of these viruses down-modulates Class I expression in a unique manner, and has been associated with spontaneous abortion. If HLA-G protects the fetus from attack by the maternal immune system, then its down-regulation, as caused by viral infection, might have disastrous consequences for the fetus. The proposed work is relevant for understanding the molecular basis of feto-maternal immune interactions, and for understanding how viral pathogens impinge on them.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI038577-03
Application #
2457844
Study Section
Special Emphasis Panel (SRC (87))
Project Start
1995-08-01
Project End
1997-08-31
Budget Start
1997-08-01
Budget End
1997-08-31
Support Year
3
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Massachusetts Institute of Technology
Department
Type
Organized Research Units
DUNS #
City
Cambridge
State
MA
Country
United States
Zip Code
02139